This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-302470, filed on Oct. 2, 2000 and No. 2001-232166 filed on Jul. 31, 2001 in Japan, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to an endoscope, or more particularly, to an endoscope having two bending portions of a first bending portion and a second bending portion.
2. Description of the Related Art
Endoscopes have an elongated insertion member thereof inserted into a three-dimensionally complexly tortuous and narrow lumen of the stomach, the intestine, or any other organ of a living tissue, or a three-dimensionally complexly tortuous and narrow hollow of a machine in conformity with the shape of the lumen or hollow. The insertion member must therefore be angled three-dimensionally finely.
For example, an endoscope described in Japanese Examined Patent Application Publication No. 5-16857 has two bending portions of a first bending portion and a second bending portion. The first bending portion is the distal portion of an elongated insertion member and has a plurality of joint pieces concatenated so that the joint pieces can rotate freely. The second bending portion is located at the proximal end of the first bending portion. A hand-held unit having a control section that is used to bend the first bending portion and second bending portion has an angling mechanism. The sole angling mechanism enables selective bending of the first bending portion and second bending portion.
However, when the insertion member of an endoscope has two bending portions, the lengths of the bending portions have a significant meaning.
For example, assume that a narrow lumen such as the lumen of the large intestine is observed. In this case, if the second bending portion that is the proximal portion is longer, when the second bending portion is bent, the bending portion including the first and second bending portions is entirely largely moved. It is therefore hard to finely adjust the position of the distal part of the endoscope. This eventually poses a problem that observation is hard to achieve.
For example, when the cardia of the stomach and its surroundings are observed by viewing the face of the cardia, the first bending portion is largely bent in an Up direction and the second bending portion is bend in a Down direction. The distal part of an endoscope may thus be made to approach the cardia. When the second bending portion is long, although the second bending portion has not fully come out of the esophagus, the whole bending portion including the first and second bending portions must be bent. It is therefore hard to bend the second bending portion. This results in unsuccessful observation.
The present invention attempts to break through the foregoing situation. The present invention aims to provide an endoscope capable of offering improved ease of observation with a second bending portion thereof bent and with a distal portion of an insertion member thereof faced a desired position.
Accordingly, an object of the present invention is to provide an endoscope offering improved ease of observation with a distal portion of an insertion member thereof faced a desired position.
Another object of the present invention is to provide an endoscope having two bending portions that can be bent independently of each other, and offering ease of bending of the same level as that an endoscope having one bending portion offers.
Still another object of the present invention is to provide an endoscope offering excellent maneuverability and making it possible to readily achieve accurate observation or treatment.
According to the present invention, there is provided an endoscope having a first bending portion and a second bending portion. The first bending portion is the distal portion of an elongated insertion member. The second bending portion is located at the proximal end of the first bending portion. The dimension of the second bending portion in the longitudinal direction of the insertion member is smaller than the dimension of the first bending portion therein.
According to the present invention, there is provided an endoscope having a first bending portion, a second bending portion, a first control member, and a second control member. The first bending portion is the distal portion of an elongated insertion member. The second bending portion is located at the proximal end of the first bending portion, and the dimension of the second bending portion in the longitudinal direction of the insertion member is smaller than the dimension of the first bending portion therein. The first control member is included in a hand-held unit proximal to the insertion member and used to bend the first bending portion. The second control member is included in the hand-held unit proximal to the insertion member and used to bend the second bending portion.
Other features of the present invention and the advantages thereof will be fully apparent from the description below.